This invention relates to the method of forming and a braided fabric having exceptional longitudinal stability. The fabric may be produced by hand, on a machine as described in co-pending patent application Ser. No. 09/008,455, filed Jan. 16, 1998, or by other known braiding machines.
Tubular braided fabrics are well known as braiding is one of the oldest forms of fabric making. Braided fabrics constructed for longitudinal stability are also well known. Known tubular braided structures which incorporate longitudinal yarns are shown in U.S. Pat. No. 3,007,497 to Shobert; No. 4,741,087 and No. 4,777,859 to Plummer; and No. 5,197,370 to Sladfelter. In each of these patents, the angularly and transversely disposed yarns are moved in an over and under relationship across the fabric. To arrange these yarns in this manner requires machinery capable of extensive manipulations. The process places portions of both yarns on each surface of the fabric which limits design capabilities and does not significantly improve stability.
Similar structures have been woven flat on triaxial looms. In U.S. Pat. No. 3,446,251 the yarns Y and Z are weft yarns which are moved in successive passes across and through warp yarns X in an over and under relationship for the construction of flat triaxial woven fabrics. This fabric is not formed of continuous yarns in a continuous motion along a longitudinal axis and is not formed as a tubular fabric.
It is an object of the instant invention to overcome these short comings of the prior art.
Another object of the invention is to form a braided structure bound together with only the longitudinal yarns.
Another object of the invention is to provide a tubular braided fabric with at least certain of its forming yarn groups restricted to a single fabric side.
It is another object of the invention to provide a braided fabric with selected longitudinal elongation.
It is another object of the invention to provide a braided fabric with exceptional longitudinal strength.
It is another object of the invention to provide a braided fabric having selectible crimp, which allows for the control of longitudinal elongation.
It is another object of the invention to provide a method of forming a fabric with the above qualities.